(B) <u>Darwin</u>, which focused on the appearance of new species as substitutes for extinct species of the same natural group, <u>making the comparison of fossil </u>and modern specimens of the same natural group.
(C) Birds that are known as "<u>Darwin's finches</u>", For example, there were three or four distinct "varieties" or species of finches on the different islands. <u>The most important differences between the species are in the size and shape of the beak</u>.
He saw the slightly different forms of finches and turtles on different islands as early stages in the development of new species from common ancestors.
(D<u>)</u> <u>He did observe that on the islands there are different forms of animals that would otherwise be similar</u>. Their attention was also directed to the differences in the shapes of the giant tortoise shells, with each island in a slightly different form.
The replacement of extinct species by modern ones, as in the case of giant armadillos and sloths, the micro-version of the same geographic replacement patterns in different islands in a chain, finches and turtles.
<u><em>The correct answers are:</em></u> <u>B, C and D. </u>